This audio amplifier is made up of an LM380N-8 IC Chip. The LM380N-8 comes in an 8 pin package. The primary advantages of the LM380 series IC's are higher output power, very low distortion and low external parts count.
The LM380N-8 audio amplifier circuit IC shown below is an 8 pin dip version of LM380N audio amplifier IC which is also available in a 14 pin dip package. The internal circuits of both ICs are almost same. Both the ICs are able to deliver output power around 2W to 2.5 watt. The audio circuit shown here is easy to build using only few external components.
The LM380 is a power audio amplifier circuit for consumer applications. In order to hold system cost to a minimum, gain is internally fixed at 34 dB. A unique input stage allows ground referenced input signals. The output automatically self -centers to one-half the supply voltage. The output is short circuit proof with internal thermal limiting.
The package outline is standard dual in - line. The LM380N uses a copper lead frame. The center three pins on either side comprise a heat sink. This makes the device easy to use in standard PC layouts. Uses include simple phonograph amplifiers, intercoms, line drivers, teaching machine outputs, alarms, ultrasonic drivers, TV sound systems, AM -FM radio, small servo drivers, power converters, etc.
It can be operated between 10 to 22 volt DC. The circuit is ideal to use as an audio amplifier with other projects you build in your lab like AM or FM receiver circuit, alarm circuit, intercom circuit, buzzer circuit etc. The 8 Ohm speaker can be replaced with an 8 Ohm headset.
The functional voltage of this unit is from 10 to 22 VDC. Use two 9 V batteries in series for an 18V supply. You can replace the 8 Ohm speaker with a set of headphones if desired.John